(1) Field of the Invention
The present invention pertains to a blower housing for a blower fan of a heating furnace or other similar types of blower applications. In particular, the present invention pertains to a blower housing constructed of a pair of end walls and a sidewall joined by seams extending around at least portions of the peripheral edges of the end walls, wherein the seams are formed in two sections positioned at angles relative to each other, the angles dividing the seam sections extending around the seams. The angles formed between the two seam sections improves the ability of the seams to resist relative movement between the sidewall and the two end walls of the blower housing due to vibrations of the sidewall and two end walls during blower operations. The seams also enable a blower housing to be constructed from a coated sidewall and a pair of coated end walls without the need for spot welds or screws along the seams joining the sidewall and end walls. What is meant by coated is a prepainted or precoated sidewall or end walls such as galvanized or aluminized walls. The particular seam construction also enables the sidewall to be joined to the pair of end walls without deforming the end walls.
(2) Description of the Related Art
Blower housings of the type pertaining to the present invention are typically employed in forced air heating furnaces. In most cases, the blower is assembled in the interior of the furnace. Ambient air is blown by the blower over heat exchangers that heat the air passed over the exchangers by the blower. The heated air is then forced from the furnace by the blower.
A typical blower housing contains a cylindrical blower fan and is constructed from a pair of housing end walls spaced at opposite lateral sides of the blower housing, and a sidewall that is connected around peripheral edges of the two end walls. The sidewall spaces the two end walls laterally from each other, and gives the blower housing a general cylindrical configuration well suited for containing the cylindrical blower fan.
In many prior art blower housings, the end walls are substantially planar around their peripheral edges. The sidewall is connected to the peripheral edges of the end walls by folded over seams formed at the opposite lateral edges of the sidewall. A portion of each sidewall seam engages against a peripheral portion of the interior surface of each end wall, and the seam is folded over the peripheral edge of the end wall so that a second portion of the seam overlaps and engages against a peripheral portion of the exterior surface of the end wall. The two portions of the seam overlapping the peripheral portions of the interior and exterior surfaces of the end wall are crimped along the peripheral edge of the end wall, thereby attaching the sidewall between the two end walls. In variants of this construction, screws are inserted through the folded seam portions or spot welds are provided along the seams to securely attach the sidewall between the two blower housing end walls.
The above described prior art construction of blower housings has been found to be disadvantaged in that in crimping the seams between the sidewall and end walls of the blower housing, the end walls of the blower housing are at times deformed during the crimping process. Moreover, the prior art seam connections between the sidewall and end walls of the blower housing will vibrate loose over a period of use of the blower housing and will produce squeaks due to relative movement between the sidewall and the end walls at the seam. Spot welds and screws have been employed along prior art seams connecting the sidewall and end walls of blower housings to prevent the seams from vibrating loose and producing squeaks. However, the use of spot welds or screws along the seams increases the expense involved in producing the blower housings. Furthermore, in blower housing constructions where the sidewall and end walls have been painted prior to their assembly, the use of spot welds along the seams connecting the sidewall to the end walls is difficult to weld and leaves weld marks along the seams that detract from the appearance of the painted blower housings.
What is needed to overcome these disadvantages associated with prior art blower housings is an improved seam construction that does not deform the housing end walls and that does not require spot welds or screws to prevent relative movement between the sidewall and end walls, thereby reducing the costs involved in producing the blower housing and enabling the blower housing to be constructed from a coated sidewall and end walls.